The 22 Key Turning Points In The History Of YouTube (GOOG)

YouTube is the world's most popular online video site, with users watching 4 billion hours worth of video each month, and uploading 72 hours worth of video every minute.

Since its inception in 2005, YouTube has grown from a site devoted to amateur videos to one that distributes original content.

It played an instrumental role during the Arab Spring, and has also helped jumpstart the careers of Justin Bieber and Korean pop sensation Psy.

Chad Hurley registers the trademark, logo, and domain of YouTube on Valentine's Day 2005

Before Feb. 14, 2005, very few people had ever even heard the name "YouTube." It was founded by former PayPal employees Chad Hurley, Steve Chen, and Jawed Karim. The idea was born at a dinner party in San Francisco about a year before the official launch.

YouTube launches its beta site in May 2005

Wow. It's amazing how much YouTube's homepage has evolved since its very first one in 2005.

The first video posted to the site, "Me at the Zoo," was only 19 seconds long

On April 23, 2005, YouTube co-founder Jawed Karim posted the very first video to YouTube, entitled "Me at the Zoo." The video is exactly how it sounds: Karim at the San Diego zoo standing in front of the elephants and talking about their trunks.